With conventionally used mobile cranes or crawler-mounted cranes a series of data is sensed in the electronic control and monitoring system. These are, for example, data with respect to the setup conditions, to the added counterweights, to the extended position of the stabilizer plates and to many other things. The respective data are sensed by different detection systems and are input automatically in part, but also manually in part. The respective setup condition of the boom is, for example, thus typically entered into the computer by the operator by hand. The computer then calculates the possible maximum load-bearing capacities with reference to the correspondingly entered values.
In another application, the extended position of the stabilizer plates is sensed by a corresponding sensor system. Here, for example, the length of a running tape measure is sensed which is secured to the telescopic end of the plate and is refracted and extended with it.
It is the object of the present application to provide a mobile crane or a crawler-mounted crane comprising a state or position detection device which unambiguously detects pre-defined states or positions and passes them reliably on to the electronic control system.
In accordance with one embodiment, this object may be solved by means of a mobile crane or of a crawler-mounted crane comprising at least one transducer in the form of a inductively acting transponder, a receiver unit for the sensing of the position of the transducer, a control device for controlling in dependence on a signal of the receiver unit, as well as a signal transmission device in the form of a databus for the transmission of the signal data from the receiver unit to the control device are used as a position detection device.
Correspondingly inductively acting transponders having receiver units are typically also called RFID systems, i.e. radio frequency identification systems. Such RFID systems are generally already known in the most varied application areas. These RIFD systems have a transponder which, on excitation by corresponding signals, inductively transmits information as an RF signal to a receiver unit. The receiver unit, which is also called a reader, contains a digital electronic system which controls the transponder such that it transmits back the information stored on it as modulated RF signals. This information received by the transponder is supplied in one embodiment via a databus to the control device of the mobile crane. In one example, a state and position detection device of this kind can be used in different positions in the mobile crane.
Since it is of special importance in a mobile crane that the detection devices of this kind work without error, for the self-check of the functioning of the receiver unit, a transponder may be fixedly installed in it in accordance with an advantageous aspect which transmits a pre-determined function signal for the continuous monitoring of the functioning of the position detection device. If therefore the specific signal transmitted by the fixedly associated transponder is no longer received here, an interference event signal is generated in the control computer so that this malfunction cannot remain unnoticed in the operation of the mobile crane.
Further preferred embodiments of the invention result from the further subordinate claims dependent on the main claim.
In accordance with a particularly advantageous embodiment variant, the position detection device can be used with a guy-rope in the form of a rope length adjustment apparatus. This length adjustment apparatus has a rope-holding apparatus for the adjustment of a desired rope length of the guy-rope, with the rope length adjustment apparatus having at least one transducer secured to the guy-rope whose positions can be sensed by the receiver unit and with the control device controlling the rope-holding apparatus in dependence on a signal of the receiver unit 1.
The mobile crane or crawler-mounted crane can advantageously have a guying for the telescopic boom which has at least one guy support supported on one of the sections, a guy-rope supported by the guy support and a rope length adjustment apparatus in accordance with the previously described solution.
The receiver unit can be arranged at the guy support. A rope winch for the hauling in of the guy-rope can advantageously be provided which is preferably arranged on the guy support and can be controlled in dependence on the signal of the receiver unit. This rope winch can form the rope-holding apparatus.
The at least one transducer can be integrated in a ring seated on the guy-rope. Such a ring can be pressed onto the rope at a pre-determined position.
Two guy supports can advantageously be provided which are spread apart in a V shape in an operating position and a guy-rope can run over each guy support, with transducers preferably being secured to each guy-rope, preferably to rope sections respectively corresponding to equal rope lengths of the guy-ropes. Due to the position detection device provided here, it can be precisely determined by how much the respective guy-rope has been tensioned by the corresponding transponders moving over the receiver devices so that the precise and symmetrical positioning of the guy supports can hereby be set.
Another preferred aspect of the invention consists of a transducer being arranged at least at one ballast element from which a signal corresponding to the ballast can be transmitted to a receiver unit.
The receiver unit can be integrated into a region of the mobile crane chassis on which the at least one weight can be placed. A plurality of receiver devices can also be arranged at corresponding positions of the mobile crane chassis which can then communicate with associated transponders after the corresponding placing on of weights. Alternatively, a receiver device can also be arranged in a portable unit which is guided along the placed-down weights by the operator in order to pick up the corresponding data from the respective transponders of the weights. These data can then, for example, be input into the control device of the mobile crane via a radio connection.
The receiver unit can also be arranged in a region of the crane boom on which the at least one weight can be suspended. Communication takes place here with the associated transponders after a corresponding suspension of the weights. These data can, as already described above, be transmitted to the control device of the mobile crane so that the precise ballast adjustment of the boom can be sensed here.
In accordance with another advantageous aspect of the invention, transducers can be arranged at the extensible stabilizer plates, with corresponding receiver units being arranged at the vehicle chassis. Transducers, i.e. transponders, are advantageously arranged at predetermined positions at every stabilizer plate so that the precise position of the support plate can be determined by the respective receiver unit. The position can be precisely determined both with respect to the sliding spars extensible horizontally to the vehicle and with respect to the vertically extensible support plates. In addition, it is possible to measure at each stabilizer plate whether it is under load.
A further preferred aspect of the invention relates to a setup element detection, for example of lattice elements of a derrick boom. A respective transducer, i.e. transponder, is arranged at the respective setup elements. After a corresponding assembly of the individual setup elements, the setup condition can be determined by reading out the signals from the transponders. For this purpose, receiver units can advantageously be arranged at the adjacent elements and are connected to the control computer of the mobile crane via a bus system. The precise geometric configuration can be determined with reference to the corresponding setup condition data in the control computer. Weight distributions within the boom can hereby be calculated in a simple manner with great precision.
Yet another embodiment variant of the invention contains a mobile transducer which cooperates with a receiver unit which is arranged at a specific position on the mobile crane in order to detect a safe position of an operator and to release predetermined actions of the mobile crane. The occupational safety of the operator is hereby substantially increased. The problem previously existed that, for example on a remote control of the crane, the operator could be hit and injured by retracting or extending stabilizer plates. Since the operator has to stand in the close region of a receiver unit through the transponder or transducer, it can now be ensured by a corresponding arrangement of the receiver unit that the operator is standing outside the danger zone. The remote control is only released in the embodiment shown here in this correspondingly defined region. This means that the operator cannot operate the blocked remote control in a region in which the transducer he is carrying does not exchange data with the receiver unit. Only in the region in which the transducer transmits its data to the receiver unit is the remote control released and thus the safety of the operator ensured.